Paul Manafort is asking the federal judge overseeing his DC-based criminal trial to toss out any of the evidence obtained by the FBI in its search of a storage unit in Alexandria, Virginia — evidence that includes materials relating to his and Rick Gates's work in Ukraine.

The request, a motion to suppress evidence, is filed to argue that evidence obtained by law enforcement — here, the FBI — was obtained as the result of an illegal search and cannot be used at trial by a prosecutor — here, special counsel Robert Mueller.

Manafort's lawyers late Friday asked that "all evidence that the government seized from the storage unit must be suppressed" — as well as other evidence that followed from that — because, they argue, the government initially searched the storage unit without a warrant, in violation of the Fourth Amendment's protection against unreasonable searches.

The lawyers, Kevin Downing and Thomas Zehnle, argue that the FBI agent who initially searched the unit on May 26, 2017, did so "after obtaining 'consent' to do so from a former low-level employee of Davis Manafort Partners, Inc." who "had no actual authority to allow the FBI Agent into the premises."

After that initial review of the storage unit — the agent did not open any of the boxes — the agent then filed an application for a search warrant, detailing the labels he'd seen on some of the boxes and how they related to items that the agent was seeking, making it "reasonable to believe that this storage unit is a collection point for Manafort's and Gates's business records from their work in Ukraine."

In the search warrant application, the agent said that the person who authorized the initial review had once worked for Davis Manafort Partners but was working for a different Manafort company, Steam Mountain, LLC. Manafort's filing refers exclusively to the individual as a "former" employee. US Magistrate Judge Theresa Buchanan issued the search warrant on May 27, and the FBI returned to the unit and executed the warrant that day.

Manafort's work in Ukraine is a key part of both of his pending criminal indictments. Manafort's indictment in DC accuses him of conspiring to hide his work on behalf of the Ukrainian government, as well as the millions of dollars in profits that he and Gates earned from that business. The Virginia indictment added new tax-related and bank fraud charges.

In Friday night's filing, Manafort's lawyers argue that by the time the FBI returned to get the documents, the search was already "fundamentally flawed" because the former employee of Davis Manafort Partners was not authorized to consent to a search of the unit.

Manafort's lawyers acknowledge that the "former low-level employee" was "named as an occupant on the lease agreement" — in fact, he is the only occupant named on the lease. They go on to argue, however, that he was so named "simply for administrative convenience and only because he happened to be the DMP employee tasked with setting up the storage lease on DMP’s behalf and moving DMP’s business records into the unit."

The lawyers claim that their argument is "bolstered" by the fact that "Mr. Manafort appears on the agreement as the only person with authorized access to the storage unit," though that appears to be a misreading of the agreement. The lease has a line for listing the "Occupant's Authorized Access Persons" — meaning people authorized by the occupant to access the unit. By the terms of the lease, the occupant was the "former low-level employee"; Manafort's was the only name listed as an authorized access person by the occupant.

Manafort's lawyers also question whether the former DMP employee's "purported consent" to the search was voluntary. They asked Judge Amy Berman Jackson to hold a hearing on the matter.

In addition to arguing that the initial search violated Manafort's Fourth Amendment rights, the lawyers argue that the warrant the government subsequently obtained was an "overbroad general warrant" and that the search itself "exceeded the warrant's search parameters" — both in violation of the Fourth Amendment.

Finally, the lawyers argue that "because other search warrants later obtained by the government incorporated the fruits of the illegal search of the storage unit" — in other words, relied upon evidence obtained from the storage unit — "all evidence obtained from those warrants must also be suppressed." That would include evidence obtained as a result of the "warrant to search Mr. Manafort’s residence," they note in a footnote.

That mention of the search of Manafort's residence is notable because his lawyers had, an hour earlier, asked for more time to file a motion that specifically would seek "to suppress the fruits of the search of his residence." Jackson had on March 11 set a Friday deadline for any motions to suppress evidence. The two-sentence motion asked for "an extension over the weekend, to and including Monday" to file the motion and provided no reason for the request. Jackson had not ruled on the motion by the time of publication.

Chris Geidner is a reporter for BuzzFeed News and is based in Washington, DC.